A rectangular park which is 105 m long and 75 m wide has a grassy walking path 2.5 m wide all around it on the inside. Find the cost of trimming the grass path at ₹18 per sq. m.

Correct option is D

Given:

Outer dimensions of the park:
Length = 105 m, Width = 75 m

Width of the path (inside border): 2.5 m

Cost of trimming grass = ₹18 per sq. m

Formula Used:

Area of outer rectangle = L × B

Area of inner rectangle = (L − 2w) × (B − 2w)

Where, L = Length ,

B = Width  , w = Width
Solution:

Area of outer rectangle

= 105 × 75 = 7875 sq. m

Area of inner rectangle

= (105 – 2 × 2.5) × (75 – 2 × 2.5) = (105 − 5) × (75 − 5) = 100 × 70 =7000 sq. m

Area of the grassy path

= 7875 - 7000 = 875 sq. m

Cost of trimming the path

= 875 × 18 = ₹15,750